Using the formula Sn = n/2(2a + (n-1)d)
Sn = sum of the series
n = how many terms
a = first term
d common difference
95 = 5/2(2a+(5-1)1)
95 = 5/2(2a+4)
95 = 10a/2 + 20/2
95 = 5a + 10
5a = 95-10
a = 85/5
a = 17
Now you can count up to the third number which is 19 or use formula
an = a+(n-1)d
where n = 3
an = 17+(3-1)1
an = 17+2
an = 19
